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Which is better for engine parts, chassis etc???? I know the custom bike guys use powdercoating a lot. Was just wondering what others in the rod scene think is best
 

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The threads I have seen on this before swear by epoxy primer, 2K primer then Colour and clear.
Once the powder coat chips your knackered.
 

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I used to work at a powder coating place and your quite right as soon as the powder coating chipps and water gets in it will start to flake off so paints a lot better .
 

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powder coat for me as we use it on bespoke JCB parts (you won't get a more hard wearing vehicle) and if the coating chips just top it up with paint as soon as.


one thing get it done right though.

also depending on what you are powdercoating/painting if you can galvanise it first then it doesn't matter if you paint or powdercoat it :tup:
 

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The threads I have seen on this before swear by epoxy primer, 2K primer then Colour and clear.
Once the powder coat chips your knackered.
My thoughts exactly, I got my Harley frame blasted and powder coated,it didnt last 6 months before it was flaking off,everytime I washed it more and more flaked off just like puff pastry I resorted to a full stripdown and 2 pack paint , it was still good when I sold the bike 4 years later. In my view powder coating is no good for exterior applications. :tdown:
 

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For most things paint is better. As others said once surface of powder coated bits is broken it will spread and keep flaking.
 

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Iv'e had powder coating done on my axle parts in the past and it was useless chipped even before I fitted some parts, also got in parts I didn't want it in, so I had to pay to have it all removed,

Wouldn't use it again.

Last weekend I helped my mate install his u/j's in his Jag powder coated drive shafts, and guess what, yes the powder coat came off when we installed the u/j's, and we where extra carefull.

So that makes two of us that won't use it again,
 

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Which is better for engine parts, chassis etc???? I know the custom bike guys use powdercoating a lot. Was just wondering what others in the rod scene think is best
Countryboy,

Just studied your original post again, and you ask

Powder Coating or Paint, which is better,

Well theres only one real way to find out FIGHT :pmsl::pmsl::rofl::giggle:
 

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I own a powder coating company in Farnworth near Bolton, we are an approved applicator which means our process is independantly checked. It is true that powder coating does chip and flake but in both instances its because the applicator has made fundamental errors or has a poor process.

Powder adherence should be equal to paint and the finish should be harder wearing and more impact resistant.

There are 2 main causes for the problems discussed,

The 1st is insufficient pre-treatment.

Just like painting the powder needs a key to adhere, this can be in the form of either a lightly sprayed etch or a dip phosphate process. As with painting, the product must be fully degreased prior to the key being applied. Degreasing is usually in the form of either a vapour degrease, or burn off ( baking the product at high temperature).

The 2nd and major reason for poor adherence is incorrect curing.

This is where the similarities of powder coating and painting differ, as soon as wet paint hits the product it has adhered. When powder is applied it is purely held on by static electricity. The product is then placed in an oven at 200deg. At this temperature the powder melts without burning, the powder melts from the outside inwards towards the product, the product acts as a heat sink stopping the powder adhereing to its surface until the product itself is up to the 200deg.

So what happens is that either due to insuffiecient curing time or poor heat distribution in the oven the product didn't get up to temperature. What you have is a finish that looks fantastic and the customer goes away happy, however; unbeknown to them it has not adhered and if knocked will chip or flake.

A good coaters will place 4" square test pieces in with a job and carry out a test which cross hatches the coating through to the metal, a special very sticky tape is then stuck over the hatched area left for a while then peeled off like a plaster. Obviously nothing should stick to the tape.

approved coaters have charts that dictate exact cure times and temperatures dependant on material type and thickness. i.e. a 1mm thick sheet steel product will take max 10 mins to fully cure. Where as 3mm sheet aluminium will take 20 mins.

Thats the basics, there is alot more to it for example: An engine block would have to be left in the oven for 3hr prior to coating then coated hot and cured for the normal 20mins, this is to ensure metal is up to temperature but powder does not discolour due lengthy oven time. coating.

Powder coating is an unbeatable surface finish if done right, this is why all external street furnature, cladding etc. is powder coated.

Hope this helps .:)
 

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Discussion Starter · #12 ·
Si apologies put it into wrong section without realising. Toddy yes your reply definetly helps. Like I said before seen powdercoating on several custom bikes and the owners have said that is as good as paint. Just wanted to see how others had faired using powdercoat on there rides. Toddy will be in touch for a chat. Will PM sunday
 

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No probs countryboy, will update post next week to explain about the three types of powder and there suitability within our hobby.
 

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I too have had problems with powder coating getting chipped then rust spreading underneath leading to sections just lifting and moisture getting trapped between the coating and the steel causeing worse rust than if the metal was just open to the elements. From what you say Toddy i guess there's a lot of companies that just dont do it properly.

another down side with powder coating as far as i'm concerned is that you cant touch it up so if you do damage it or want to carry out a modification to a chassis etc you cant just repair a localised section like you can with paint.

i swear by epoxy primer on pretty much everything i paint, it has fantastic a adhering qualities on bare steel, aluminium ets and is a great barrier coat on bodywork where your doing repairs where your having to paint over old layers of paint. it's been about 11 years since i used etc primer
 

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I too have had problems with powder coating getting chipped then rust spreading underneath leading to sections just lifting and moisture getting trapped between the coating and the steel causeing worse rust than if the metal was just open to the elements. From what you say Toddy i guess there's a lot of companies that just dont do it properly.

another down side with powder coating as far as i'm concerned is that you cant touch it up so if you do damage it or want to carry out a modification to a chassis etc you cant just repair a localised section like you can with paint.

i swear by epoxy primer on pretty much everything i paint, it has fantastic a adhering qualities on bare steel, aluminium ets and is a great barrier coat on bodywork where your doing repairs where your having to paint over old layers of paint. it's been about 11 years since i used etc primer
Sorry to hear you had problems, the consequences of a poor powder coating job can be painful often requiring full strip downs and alot of work just to get back to where you were. Yes, Unfortunately there are alot of companies that don't do it properly, they fail to apply any key, degrease with thinners and insufficiently cure. Hopefully this thread will help RnS's users avoid a bad job, talk with the coaters first, confirm the process they will use, provide the coater with additional bogus part or pre-agree a test piece, carry out your own adherence test using a stanley knife to cut the hatch and good sticky tape.

Powder coating can be cut back, touched up, buffed and polished just like paint, for good colour match ask the coaters to provide a touch up that has been made by the same manufacturer as the powder (100% exact colour match is unlikely). Touch up requests shouldn't be a problem to a coaters so don't be afraid to ask. Theres no way of powder coating a localised area, the touch up is paint.

I have nothing against wet painting products, its horses for courses, many parts that have cores etc that will not withstand 200 deg. Products have to be fully stripped or blasted for the powder coating process; therefore; as you say its great for where your having to paint over old layers of paint.
The finished product should be visually identical, the correctly powder coated product will be more robust.
 

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Hi Toddy
Great explanation post, same here in the states, you have to do your homework before committing to any one coater. We have a few larger companies and size in this industry did not seem to matter.
The outfit even contracts with government jobs ( army , navy) & so on. That sad to say was the worst job we had experienced.
We have been using a company local to my shop that I never knew existed . The son took over from the dad and has a humble size shop. 10 thousand square foot, shop.
I stopped down the first time to collect information on what I was in need of , and the son ask me to take the time to tour with him threw the shop.
This was great , I really was surprised on how he explained each step , showed me product for different companies like bike manufactures (4 wheelers & trail bikes) and of course midget racing and late model chassis. He also showed me were they do hot coats exhaust for the bikes and custom headers. I have had a few items coated so far and happy with the results. I think what satisfies me the most is the personal attention when working with the shop on colors and coordinating the job it's self...... That in it's self was reasuring to know if I do have a problem i have back up and not get the shuffle till I just go away.... :)
 
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